A ubiquinone plays an extremely important role as an essential constituent component of the mitochondrial electron transport system on the production of ATP that is a high-energy phosphate compound. Hitherto, for the purpose of activating the myocardial function, CoQ10 has been prescribed as a remedy of congestive heart failure. In recent years, attention to an antioxidative capacity that is another important in vivo action is increasing, and CoQ10 has occupied a very important position in the market of health foods, too.
CoQ10 is a crystalline powder having a melting point of from 50 to 52° C. and can be used as a raw material of medicines and health foods in various product forms such as tablets, hard capsules, soft capsules and the like even as it stands.
However, the crystalline powder of CoQ10 involves such problems in view of preparations concerning handling properties and fluidity that it has a low bulk density and is bulky; and that its aggregation properties and attachment properties are strong. For that reason, there are involved such problems that it is difficult to design and produce capsule preparation products with a high filling factor; and that the production cannot be stably carried out.
Then, for the purpose of solving these problems concerning the production of CoQ10-containing preparations, various technologies have been proposed. For example, there are disclosed a method of mixing a medicine and an additive containing a fluidity modifier such as light anhydrous silicic acid and the like and subsequently grinding the mixture (see, for example, Patent Document 1); a method of granulating a mixed powder containing a low-melting point material and an adsorbing carrier and fluidizing the obtained granulated material at an air supply temperature of a melting point or higher by using a fluidized bed dryer (see, for example, Patent Document 2); and a method of spraying a prolamin protein in a solution state while mixing a CoQ10 powder and an excipient upon being fluidized by a fluidized bed apparatus, thereby obtaining a powder (see, for example, Patent Document 3).
However, all of these methods are those in which the fluidity of the CoQ10 powder is improved by using an additive such as an excipient, a binder and the like, thereby contriving compactification, but they do not at all touch on a technology for improving powder properties of CoQ10 without using an additive.